As an example of a medical image diagnostic apparatus, there is a magnetic resonance imaging (MRI) apparatus. A conventional MRI apparatus includes a bed device. By placing an object on the top plate of the bed device and moving the top plate in the long axis (longitudinal) direction, the object is carried into the imaging space of the gantry. In addition, positioning of an imaging part is performed by adjusting the position of the top plate in the long axis direction. Depending on the imaging method, a method of moving the top plate in the long axis direction even during imaging in order to image the whole body of the object is also known.
In many conventional apparatuses, a driving mechanism for moving the top plate into the imaging space is provided in the bed device (for example, PTL 1). In this configuration, the transport distance of the top plate depends on the length of the bed in the long axis direction. Therefore, it has been difficult to transport the top plate over a distance larger than the length of the bed, for example, when imaging the whole body of the object.
PTL 2 proposes an MRI apparatus including a driving mechanism on the gantry side. PTL 2 proposes a configuration in which a carriage including a driving mechanism is disposed on the gantry side and a wheeled top plate is connected to the hook of the carriage so as to be drawn into the gantry. Since the driving mechanism is mounted on the gantry side, the transport distance of the top plate does not depend on the length of the bed.